Artificial limb



A. PECORELLA, V. PATRICOLO AND F. H. APEL.

1 ARTIFICIAL LIMB.

- APPLICATION FILED OCT. 23, I919.

Patented Jun 7, 1921.

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A. PECORELLA, v. PATRIC-OLO, AND F. H. APEL.

ARTIFICIAL LIMB.

APPUCATlON FILED OCT, 23 1919. 1,380,835. PatentedJune 7, 1921..

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ALBERTO PECORELLA AND VINCENT PATRICOLO, OF BUFFALO, AND FREDERICK H.AIEL, OF A'II-IOL SPRINGS, NEW YORK.

ARTIFICIAL LIMIB.

Specification of Letters Patent.

Patented June 7, 1921.

Application filed October 23, 1919. Serial No. 332,698.

the county of Erie and State of New York,v

and FREDERICK H. APnL, a citizen of the United States, residing at AtholSprings, in the county of Erie and State of New York, have invented newand useful Improvements in Artificial Limbs, of which the following is aspecification.

This invention relates to an artificial 'hand and has for its objectsthe provision of improved means for operating the fingers so that theycan adapt themselves to articles of irregular shape and securely holdthe same, to provide improved means for turning the wrist and the partsmounted therein about a longitudinal axis, to improve the means wherebythe palm is turned laterally, and to improve the operating mechanism ofthe several parts in various details of construction.

In the accompanying drawings: Figure 1 is a vertical longitudinalsection of an artificial limb embodying our improvements, the sectionbeing ta ken perpendicular to the plane of the palm of the hand and online 1 -1, Fig. 2. Fig. 2 is an elevation, partly in section, of theartificial limb viewed from the palmside of the hand. Fig. 3 is asectional view similar to Fig. 2, showing more particularly themechanism for turning the wrist relatively to the palm and turning thepalm laterally relatively to the wrist. Fig. 4 is a fragmentaryhorizontal section takenon line 44, Fig. 1. Figs. 5 and 6 are horizontalsections taken on lines 5-5 and 66, Fig. 3, respectively.

Similar characters of reference indicate corresponding parts in theseveral views.

As shown in the drawings, our improvements are embodied in anarticficial limb having a forearm-section 10 which may be attached tothe stump of the real arm in any suitable manner, a wrist 11 which ispivotally connected at its rear end with the front end of the forearm soas to be capable of turning relatively thereto about a longitudinal axisa palm 12 which is pivotally connected at its rear end with the frontend of the wrist by a transverse pin 13 so as to be capable of turninglaterally relatively to the palm, a plurality of digits, the fingers ofwhich consist each of a first section '14:

pivotally connected with the palm by a pin 15 a second section 16pivotally connected w th the first section by a pin 17, and a thirdsection 18 pivotally connected with the second section by a pin 19, anda thumb comprislng a first or inner section 20 pivoted on the palm by apin 21 and a second or outer section 22 pivoted on the first section bya pin 23. All of these several members are preferably constructed ofhollow or tubular form in any suitable and approved manner so that themechanism for operating the same may be located in the interior thereof.

Inasmuch as the means for actuating the several fingers for folding orclosing and unfolding or opening the same are alike the followingdescription applying to one of them Will apply to all of the severalfingers.

The first finger section may be turned about the pin 15 either into itsopen or closed position. 120 represents a first lever of elbow formwhich is fulcrumed by a pin 121 on the second finger section outwardlybeyond the pivotal connection 17 and which has its inner arm pivotallyconnected by a pin 122 with the outer front edge of the palm, while itsinner arm is connected by a link 24 with a p1n.25 arranged on the thirdfinger section outwardly beyond the pin 19. This connectlon between theseveral finger sections and the palm causes the second and third fingersections to fold and unfold in unison with the first section forgrasping and rcleasing an article or for other purposes.

lVhen free or released, each finger is folded or moved into its closedposition by yielding means which in the preferred form comprise a sprlng26 composed of a plurality of leaves which are curved and bear at theirinner ends against the inner front edge of the palm while their outerends are secured to a hub 27 which is loosely mounted on the pin 15 butsecured to the adjacent part of the first finger section so as to turntherewith. The opening movement of the fingers is effected by a shiftingbar 28 arranged lengthwise in the first finger section and the adjacentparts of the palm and second finger section and pivotally connected atits front end with the pin 121 while its lower end is connected with apull cord or line 29 which latter upon bein drawn backwardly ordownwardly causes t e shifting bar to be raised or moved forwardly andthe finger sections to be unfolded, while upon relaxing the pull on thecord 29 the finger sections'will be folded by the spring 26. The pullcords of the several fingers pass around a roller or sleeve 30 on thepin 13 which prevents undue wear on these cords and at their rear endsthe several finger opening cords pass through an opening 32 on the innerside of the forearm and are connected to a main or common operating line31 whereby the finger opening cords may be operated in unison by pullingon this main line.

Means are provided for locking the fingers in their open position. thesemeans being preferably so organized that the fingers may be unlocked bythe initial pull on the lines 28 for opening the fingers. As shown inFigs. 1-at, these means are constructed as follows:

33 represents a segmental detent ratchet formed on the hub 27 of eachfirst finger section and having each of its teeth preferably providedwith an abrupt inner side and an inclined outer side. Each of theseratchets is adapted to be engaged by a detent which preferably comprisestwo dogs or pawls 34L arranged side by side and pivoted on a rod 35which is mounted transversely on the palm, each pawl having preferablytwo teeth which are arranged out of line with the corresponding teeth ofthe companion pawl and thereby reducing the length between the steps atwhich the segment may be caught and locked without making the teeth onthe ratchet or the detent pawls unduly fine and thereby increasing thestrength and durability of the locking device. Each of the detent pawlsis yieldingly held in engagement with the respective detent ratchet by aspring 36 bearing against the pawl and secured to the adjacent outerfront part of the palm. The pair of detent pawls associated with eachratchet are disengaged from the same by a releasing arm 37 pivoted onthe rod and having a coupling pin 38 which passes through correspondingslots 39 in the pair of detent pawls 34;. In the preferred constructioneach coupling pin 38 passes through two pairs of detent pawls associatedwith two of the detent ratchets, as best shown in Figs. 3 and 4. Thepull cord for each finger is provided in its front part with a loop 40which passes from the shifting bar 28 forwardly and outwardly around aguide pulley or roller 41 on the coupling pin 38 of the adjacent pair ofdetent pawls, whereby upon pulling backwardly on the cord 29 the firsteffect of this pull will be to disengage the detent pawls from theratchet and release the latter. so that during the subsequent orcontinued pull on this cord the shifting bar of each finger will bemoved forwardly and the finger sections associated therewith will beunfolded. This disenleasing arm 37 with a stop 42 on the palm wall,after which the further pull on the opening lines 29 causes the fingersto unfold. By employing a pin-and-slot connection between the releasingarm and the respective pair of detent pawls the latter are free to adaptthemselves individually to their ratchet but these pawls are compelledto recede together from the ratchet when the releasing arm is operatedfor this purpose.

ll'hile the detent pawls are thus disengaged from the i'atchets of theseveral fingers, the pull on the line 29 is relaxed sufficiently topermit the springs 26 to fold until they grasp the article desired, andthen the pull on these lines is entirely removed so as to permit thepawls to engage the ratchets and lock the finger sections in whateverposition they may ccupy, thereby preventing the fingers from unfoldingat this time and causing them to maintain a firm hold on the article.Inasmuch as the closing movement of the finger sections is effected bythe individual springs 26 each finger closes or folds as much as ispossible against the article. It is thus possible for the severalfingers t close a greater or lesser extent independently of each other,which permits the fingers to individually adapt themselves toirregularlyshaped articles and hold the same firmly with the samefacility as regularly shaped articles. When it is desired to release thearticles it is only necessary to pull on the several lines 29 when allthe fingers will be swung into their open or unfolded position.

The mechanism for closing or folding and opening or unfolding thesections of the H0 thumb is constructed as follows:

43 represents a longitudinal shifting bar pivotally connected at itsfront end by a pin 4 with the inner thumb section while its rear end isconnected by a pull line 45 115 with the adjacent finger section pullline 29 sons to operate in unison therewith. The thumb pull line isconstructed in the form of a forwardly extending loop which passesaround a support 47 having preferably the form of a guide roller. 48represents a link pivotally connected at its rear end by a pin 49 withthe palm while its front end is pivotall y connected by a pin 50 withthe inner part of the outer thumb section. Upon drawing backwardly onthe thumb pull line 45 the shifting bar 43 is moved forwardly, causingthe inner section of the thumb to swing outwardly while at the same timethe outer section of the thumb is swung inwardly by the link 48. "Whenthe inner thumb section 20 is swung inwardly the outer section 22 isswung outwardly relatively to the fingers. In this way the naturalmovement of the hand is simulated in that the tip of the thumb swingsslightly away from the palm of the hand while the fingers are foldlngand thus cause the fingers and thumb to close around or adapt themselvesto the object to be grasped in a manner closely resembling the action ofa human hand.

The folding action of the thumb sections is effected when the latter arefree by means of a spring 51 preferably of leaf form, which is securedat its outer end to a hub 52 which is mounted on the rear end of theinner thumb section, so as to turn therewith while its inner end bearsagainst an abutmelnt pin 46 on the adjacent part of the pa in.

For the purpose of locking the thumb sections, against unfolding whilean article is grasped by the hand, a locking device is provided whichpreferably consists of a segmental ratchet 53 formed on the hub 52, adetent pawl 54 pivoted on the pin 49 and carrying the roller 47, aspring 55 mounted on the palm and bearing against the pawl 54 for movingthe same into engagement with the ratchet 53, and a stop 56 arranged onthe palm and adapted to be engaged by the pawl 54 for limiting itsmovement away from the ratchet.

Upon pulling on the lines 29 and 45 for adapting the hand to an articleto be grasped, the first effect of the line 45 is to withdraw the pawl54 from the ratchet 53 and thus permit the inner section to be swunginwardly by the spring 55 and the outer thumb section to be swungoutwardly by the link 48 upon partly relaxing the pull on these lines.When the thumb and finger sections have reached the desired position,the pull on the lines 29 and 45 is fully relaxed, thereby permitting thedetent pawls of the fingers and thumb to engage their respectiveratchets and hold the fingers and thumb sections in their foldedposition.

The pivotal connection between the wrist and forearm for turning thesemembers about a longitudinal axis relatively to each other referablycomprises a longitudinal pivot olt 57 passing through correspondingopenings formed centrally in two plates 58, 59 which are mounted on theopposing ends of the forearm and wrist, the head 60 and nut 61 of saidbolt bearing against the opposite sides of said plates, as shown in Fig.3. Near the margins of these plates their opposing surfaces are providedwith annular ball races which receive a row of balls 62 whereby therotary movement of the wrist is relieved of undue friction, noise andwear.

The plates 58, 59 are provided with corresponding openings 63,preferably of segmental form through which the pull lines 29 pass andwhich permit the forearm and wrist to turn relatively to each otherwithout interference from said lines.

Means are provided for turning the wrist relatively to the forearm andlocking the same in various positions relatively to each other withoutrequiring the use of a natural hand for this purpose. The preferred formof these means as shown in the drawings comprises a longitudinaladjusting lever 65 pivoted by a swivel joint on a bolt 64 to the forearmso as to sw' g crosswise relatively thereto and having a rear arm 65projecting through an opening 66 in the forearm to the exterior thereofwhile its front arm 67 projects through a circumferential slot 70 in theforearm plate 58 and into a radial slot 71 in the wrist plate 59. Theinner edge of the slot 70 is provided with a plurality of notches 72which are arranged in a circumferential row and the front arm 67 of thewrist adjusting lever is held in engagement with one or another of thesenotches by a spring 73 which connects the front arm 67 with the adjacentpart of the forearm. lVhen it is desired to turn the wrist relatively tothe forearm, the rear arm 65 of the wrist shifting lever is first movedinwardly and then pressed sidewise, thereby first unlocking this leverfrom the notched edge of the slot 70 and then turning the wristrelatively to the forearm. After the wrist has been turned the requiredextent the pressure against the rear arm 65 is released, whereby thespring 73 draws its front arm 67 into engagement with the adjacent notch72 and locks the wrist against turning out of this position.

Means are provided for rocking the palm laterally relatively to thewrist and holding the same in various positions relatively to eachother, which means are constructed as follows:

74 represents an adjusting lever projecting laterally through acircumferential slot 75 in the rear part of the wrist and providedoutside of the latter with a head or handle 76 while its inner end ispivoted by a swivel joint to the front end of a screw 77 which issecured axially to the bolt 57 which .couples the plates 58, 59. Thisadjusting lever is provided with a slot or opening 78 which receives thelower or rear end of a shifting arm 79, the latter being pivoted at itsupper or front end on the wrist by a pin or screw 80 so as to permit theshifting arm to swing radially relatively to the axis Y of the wrist butcompelling the same to turn bodily with the wrist about the pivotalconnection between the palm and the wrist. The upper side of the slot 78is constructed to form a segmental row of notches 81 and the upper sideof the adjusting arm is provided with a tooth 82 which is yieldinglyheld in engagement with one or another of these notches by a spring 68which connects the adjusting lever 74 with the shifting arm 79. 1

When it is desired to tilt the palm more or less the adjusting lever74.- is first pressed backwardly or downwardly to disengage the samefrom the respective notch 81 and then turned circumferentiallyrelatively to the wrist in one direction or the other, which movement istransmitted to the palm by the shifting arm 79. \Vhen the palm hasreached the desired position the adjusting lever 74 is released andpermitted to interlock with the adjacent notch 81 by the spring 68,thereby holding the palm in its adjusted position. By ivoting theshifting arm 79 on the palm, tlie same is free to follow the adjustinglever 74 as the same swings around the axis of the pivotal connectionbetween the wrist and forearm without producing any cramping action ofthe parts.

The operation of the adjusting levers -67 and 74: may be effected byengaging the same with any object such as the body of a person, or thesurface of a table, chair or the like, thus enabling this adjustment tobe effected without the use of any hand. A change of position of thefingers and thumb is thus possible in order to simulate a natural handwithout attracting the attention of other persons, and thereby avoidingthe annoyance and embarrassment usually attending the adjustment ofartificial hands.

We claim as our invention:

1. An artificial limb comprising a palm, a finger pivoted on said palm,and means operating constantly to turn said finger into a closedposition relatively to said palm comprising a hub mounted on the finger,and a leaf spring secured at one end to said hub and engaging itsopposite end with said palm.

2. An artificial limb comprising a palm, a finger pivoted on said palmand having a plurality of pivotally connected sections, and means forunfolding said finger sections comprising a shifting bar connected atits front end with said finger sections, and a pull line connected withthe rear end of said bar.

3. An artificial limb comprising a palm, a finger pivoted on said palmand having a plurality of pivotally connected sections, and means forunfolding said finger sections comprising a shifting bar connected atits front end with said finger sections, a pull line connected with therear end of said bar and having a forwardly extending loop, and asupport around which said loop passes.

4. An artificial limb comprising a palm, a

finger pivotally connected with said palm and having a plurality ofpivotally connected sections, a shifting bar connected with the fingersections, a pull line connected with said bar and having a forwardlyextending loop, a ratchet connected with the rearmost finger section, adetent pawl engaging said ratchet, and a guide roller which is movablebodily with said pawl and around which said loop passes.

5. An artificial limb comprising a palm, a finger pivotally connectedwith said palm and having a lurality of pivotally connected sections, as ifting bar connected with the finger sections, a pull line connectedwith said bar and having a forwardly extending loop, a ratchet connectedwith the rearmost finger section, a detent pawl engaging said ratchet, aguide roller which is movable ,bodily with said pawl and around whichsaid loop passes, and a stop for limiting the movement of said detentpawl away from said ratchet.

6. An artificial limb comprising a palm, a finger pivotally connectedwith said palm and having a plurality of pivotally connected sections, ashiftin bar connected with the finger sections, apull line connectedwith said bar and having a forwardly extending loop, a ratchet connectedwith the rearmost finger section, a detent pawl engaging said ratchetand provided with a slot, a releasing arm provided with a pin engagingwith said slot, a roller arranged on said pin and receiving said loop,and a stop which limits the movement of said arm and pawl away from saidratchet.

7. An artificial limb comprising a palm, a finger pivotally connectedwith said palm and having a plurality of pivotally connectcd sections, ashifting bar connected with the finger sections, a pull line connectedwith said bar and having a forwardly extending loop, a ratchet connectedwith the rearmost finger section, a pair of detent pawls havingdifferently. arranged teeth engaging the ratchet and provided withslots, a releasing arm provided with a coupling pin arranged in saidslots, a guide roller arranged on said pin and receiving said loop, anda stop for limiting the movement of said arm away from said ratchet.

8. An artificial limb comprising a palm, a thumb having an inner sectionpivoted to said palm and an outer section pivoted on said inner section,a shifting bar connected at its front end with said inner section, and alink connecting said palm with said outer section.

9. An artificial limb comprising a palm, a thumb having an inner sectionpivoted to said palm and an outer section pivoted on said inner section,a shifting bar connected at its front end with said inner section, a

link connecting said palm with said outer section, and a pull lineconnected with said shiftin bar.

10. n artificial limb comprising a palm, a thumb having an inner sectionpivoted to Said palm and an outer section pivoted on said inner section,a shifting bar connected at its front. end with said inner section, alink connecting said palm with said outer section, a pull line connectedwith said shifting bar and having a forwardly extending loop, and asupport around which said loop passes.

11. An artificial limb comprising a palm, a thumb having an innersection pivoted to said palm and an outer section pivoted on said innersection, a shifting bar connected at its front end with said innersection, a link connecting said palm with said outer section, a pullline connected with said shifting bar and having a forwardly extendingloop, a. roller around which said loop passes, a spring operating tofold said inner section, a ratchet connected with the inner section, adetent pawl engaging said ratchet and carrying said roller, a spring formoving said pawl toward said ratchet, and a stop for limiting themovement of said pawl away from said ratchet.

12. An artificial limb comprising a-wrist, a palm pivoted on said wristso as to swing laterally relatively thereto, and means for adjustingsaid palm comprising an adjusting lever pivoted on the wrist, and ashifting arm mounted on the palm and engaging with said lever.

13. An artificial limb comprising a wrist, a palm pivoted on said wristso as to swing laterally relatively thereto, and means for adjustingsaid palm comprising an adjusting lever pivoted on the wrist andprovided with an opening, and a shifting arm engaging one end with saidopening and pivoted at its opposite end to said palm so as to be free toswing radially relatively to said lever but compelled to turn with thepalm about the axis of the latter.

14. An artificial limb comprising a wrist, a palm pivoted on said wristso as to swing laterally relatively thereto, and means for adjustingsaid palm comprising an adjusting lever pivoted on the wrist andoperatively connected with said palm, said wrist being provided with arow of notches with which said lever is adapted to engage.

15. An artificial limb comprising a wrist provided in its side with aslot having one of its circumferential edges constructed to form a rowof notches, a palm pivoted on said wrist to swing laterally relativelythereto,

an adjusting lever pivoted by a swivel con-- nection to said wrist andprojecting through said slot, a shifting arm pivot-ally connected at oneend with said lever and pivoted at its opposite end on said palm so asto be capable of swinging radially relatively to said lever butcompelled to turn with said palm about the axis of the latter, and aspring connecting said arm and lever and operating to hold the latteryieldingly in engagement with one of said notches. 1

16. An artificial limb comprising a forearm, a wrist pivoted on saidforearm to turn about the longitudinal axis of the same, and means foradjusting said wrist relatively to said forearm comprising a leverpivoted on said forearm and having one end projecting on the exterior ofthe same while its other end is opcratively connected with said wrist.

17. An artificial limb comprising a forearm, a wrist pivoted on saidforearm to turn about the longitudinal axis of the same, and means foradjusting said wrist relatively to said forearm comprising a leverpivoted by a swivel joint on said forearm and having a rear armextending to the exterior of the forearm, a plate arranged on theforearm and provided with a row of notches, a plate arranged on thewrist and provided with a radial slot which is engaged by the front armof said lever, and a spring connecting said lever and forearm andoperating to hold said front arm yieldingly in engagement with saidnotches.

ALBERTO PECORELLA. VINCENT PATRICOLO. FREDERICK H. APEL.

